Three-stage menu processing for digital disc recorder

ABSTRACT

A method for real time generation of menus in a DVD recorder. The method includes the steps of providing a template menu having one or more dummy buttons, activating a marking command during a video data recording session, and in response to the marking command, modifying the template menu by assigning to the dummy button a valid flow control command for accessing the video data which has been recorded.

This application claims the benefit under 35 U.S.C. § 365 ofInternational Application PCT/US00/29931, filed Oct. 30, 2000, whichclaims the benefit of U.S. Provisional Application 60/164,793, filedNov. 10, 1999.

BACKGROUND OF THE INVENTION

1. Technical Field

The inventive arrangements relate generally to methods and apparatusproviding advanced operating features for audio only, video only andboth video and audio programs recorded on disc media, for examplerecordable digital video discs, hard drives and magneto optical discs.

2. Description of the Related Art

Various devices have been developed to enable consumers to record videoand/or audio programs for later presentation. Such devices include taperecorders, video cassette recorders, recordable compact discs, and mostrecently, recordable digital video discs (DVD). Hard drives and magnetooptical discs have also been used.

A DVD that can be recorded on only once, and thereafter is essentially aDVD read only memory, is referred to by the acronym DVD-R. The acronymDVD-R is also used generally to refer to the write-once, or record-once,technology. Several formats are available for DVD's to be recorded on,erased and re-recorded; that is, overwritten or rewritten. These arereferred to by the acronyms DVD-RAM, DVD-RW and DVD+RW. As of this timeno uniform industry standard has been adopted. The acronyms DVD-RAM,DVD-RW and DVD+RW are also used generally to refer to the respectiverewritable technologies. Reference herein to rewritable DVD technology,devices and methods is generally intended to encompass all of thestandards which are now being used, as well as those which may bedeveloped in the future.

In many cases, the program presentations are recorded in the viewerand/or listener's absence, for presentation at a later, more convenienttime. This is referred to as time shifting the program. At other times,a program is being viewed and/or listened to without being recorded, andwith out any interest in a recording, but the viewer's and/or listener'sattention is interrupted, for example by a telephone call or anunexpected visitor. If the viewer and/or listener is watching atelevision program, for example, and has a cassette tape in a VCR, orcan retrieve and load such a cassette tape quickly, the program can berecorded. However, the viewer and/or listener cannot view and/or listento the program in its entirety, and in a proper time sequence, untilafter the recording has been completed. The time to completion of therecording can be short or long, depending on the length of the program.

Although rewritable DVD technology is generally available, operation islimited to such basic functions as play, record, fast forward reverseand stop. Pause is available, but only as a counterpart to pauseoperation in a VCR, for example interrupting the play back of aprerecorded program or interrupting the recording of a viewed program toeliminate commercials from the recording. Unlike computer hard drives,recordable DVD devices have a very significant additional function,which is playing back prerecorded DVD's. Thus, there is an economicincentive to develop rewritable DVD technology, including methods anddevices, that can be used instead of a computer hard drive. It is achallenge to provide such devices with improved, advantageous featureswithout compromising the goal of decreasing costs and increasing sales.

DVD technology allows the use of a variety of advanced features,including for example the ability to seamlessly branch from one part ofa video presentation to another. In order to accommodate this, as wellas other advanced features, the DVD-Video standard permits on-screenmenus to be used. The menus permit users to control the videopresentation by activating buttons appearing on a display screen. Forexample, menus allow users to navigate through the various videopresentation contained on a disc, select from multiple programs, selectdifferent versions of the video presentation on the disc, and operateother advanced DVD features. Menus can also be used to navigate throughinteractive video programing which may be provided on the disc. The DVDstandard also permits the use of sub-menus which may offer the userother control or selection options beyond what may be available in amain menu.

Menus play a key role in navigation of a disk. However, for a real-timerecording device, such as DVD-RW, DVD+RW, DVD-RAM and Streamer, justname a few, it is very difficult to prepare and record menus inreal-time. In particular, the creation of a menu normally requires auser to know certain information. For example, a menu for navigatingthrough a series of video presentations or recordings requires the userto know what the video presentation will be. Such information isnecessary in order to properly identify each such presentation in themenu description or in text associated with the navigation buttons.However, users often do not know what they will record on a disk priorto such recording. Further, creation of a menu requires a user to knowin advance where on the disc a particular presentation is recorded.Without such information, it is impossible to identify the location onthe disc to which a button should cause the DVD player to jump whenactivated.

Going back after various video recording sessions to insert a menu isalso a problem. Such an approach requires a user to play back or jumpthrough the recorded video to try to locate the particular presentationto which a navigation button will cause the player to jump. Since theexact location of the desired video presentation is unknown, this can bea very tedious process.

SUMMARY OF THE INVENTION

A method for real time generation of menus in a DVD recorder isdisclosed. The method includes the steps of providing a template menuhaving one or more dummy buttons, activating a marking command during avideo data recording session, and in response to the marking command,modifying the template menu by assigning to the dummy button a validflow control command for accessing the video data at a timecorresponding to said activating step.

According to one aspect, the method can include the step of storing thetemplate menu on the DVD prior to the recording session. According toyet another aspect, the method can include the step of controlling adisplay parameter of the dummy button responsive to the marking commandto make the dummy button visible. According to still another aspect, themethod can include configuring the template menu with a selected numberof dummy buttons responsive to a user input.

The method can include the step of modifying the template menu after thevideo data recording session. For example, a button language, buttonappearance, button text, menu name and menu background can be modified.Alternatively, the modifying step can include changing the appearance ofa button to a thumb-nail image. For example, the thumb-nail image can bea scene determined by the video data recorded during the video datarecording session. According to yet another alternative, the modifyingstep can include deleting a button.

According to an alternative embodiment, a system is provided for realtime generation of menus in a DVD recorder. The system includes DVDrecording hardware with suitable processing capabilities for providing atemplate menu having one or more dummy buttons. The system also providesfor activating a marking command during a video data recording session,and in response to the marking command, modifying the template menu byassigning to the dummy button a valid flow control command for accessingthe video data.

According to one aspect, the system can store the template menu on theDVD prior to the recording session. According to yet another aspect, thesystem can control a display parameter of the dummy button responsive tothe marking command to make the dummy button visible. According to stillanother aspect, the system can configure the template menu with aselected number of dummy buttons responsive to a user input.

The system can modify the template menu after the video data recordingsession. For example, a button language, button appearance, button text,menu name and menu background can be modified. Alternatively, the systemcan modify the appearance of a button to appear as a thumb-nail image.For example, the thumb-nail image can be a scene determined by the videodata recorded during the video data recording session. According to yetanother alternative, the system can delete a button when the button isno longer needed.

According to a further aspect of the invention, if the number of buttonsnecessary to access the various video segments exceeds the amount ofspace practically available on the menu, then a second menu screen canbe automatically added to include the additional buttons. The secondmenu screen can be accessed, for example, by a “next menu” button whichcan be included on the first menu screen.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a rewritable DVD device that can beprovided with one or more advanced operating features in accordance withthe inventive arrangements.

FIG. 2 is a diagram useful for illustrating the spiral track on arewritable DVD.

FIG. 3 is a diagram useful for explaining the organization of videodisc.

FIG. 4 is a diagram useful for illustrating a blank menu used inaccordance with the inventive arrangements.

FIG. 5 is a diagram useful for illustrating a menu with a single buttonin accordance with the inventive arrangements.

FIG. 6 is a diagram useful for illustrating a menu with six buttons inaccordance with the inventive arrangements.

FIG. 7 is a diagram useful for illustrating a menu in which the buttonsand menu title have been modified in accordance with the inventivearrangements.

FIG. 8 is a flow chart useful for illustrating the process according tothe inventive arrangements.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Recordable DVD Device

A device 100 for implementing the various advanced operating features inaccordance with the inventive arrangements taught herein utilizes arewritable disc medium 102 in accordance with the inventive arrangementsis shown in block diagram form in FIG. 1. The rewritable disc medium 102is embodied as a rewritable DVD in the illustrated embodiment. In manyinstances, as will be noted, the rewritable disc medium can also be, forexample, a hard drive or a magneto optical disc (MOD). An example of aMOD is a mini-disc. In many instances, the inventive arrangements areapplicable to video or audio or both video and audio.

The device 100 is capable of writing onto and reading from the discmedium, in this example, a rewritable DVD 102. The device comprises amechanical assembly 104, a control section 120, a video/audio inputprocessing path 140 and a video/audio output processing path 170. Theallocation of most of the blocks to different sections or paths isself-evident, whereas the allocation of some of the blocks is made forpurposes of convenience and is not critical to understanding theoperation of the device.

The mechanical assembly 104 comprises a motor 106 for spinning the DVD102 and a pickup assembly 108 that is adapted to be moved over thespinning disc. A laser on the pickup assembly burns spots onto a spiraltrack on the disc or illuminates spots already burned onto the track forrecording and playing back video and/or audio program material. Forpurposes of understanding the invention, it is irrelevant whether thedisc is recordable on one or two sides, or in the event of adouble-sided recording, whether the double-sided recording, orsubsequent reading from the disc, takes place from the same side of thedisc or from both sides. The pickup and the motor are controlled by aservo 110. The servo 110 also receives the Playback Signal of data readfrom the spiral track of the disc 102 as a first input. The PlaybackSignal is also an input to an error correction circuit 130, which can beconsidered part of the control section or part of the video/audio outputprocessing path.

The control section 120 comprises a control central processing unit(CPU) 122 and a navigation data generation circuit 126. The control CPU122 supplies a first input signal to the navigation data generationcircuit 126 and the servo 110 supplies a second input signal to thenavigation data generation circuit 126. The servo can also be consideredpart of the control section. The navigation data generation circuit 126supplies a first input signal to the multiplexer (MUX) 154, which formspart of the video/audio input processing path 140. The output of the MUX154 is an input to an error correction coding circuit 128. The output ofthe error correction coding circuit 128 is a recordable input signalsupplied to the pickup 108, which will be “burned” onto the spiral trackof the disc 102 by the laser.

The control CPU 122 also preferably has access to the data contained inthe track buffer 172 and record buffer 152 as shown in FIG. 1. CPU 122can delete, modify, and reformat video data stored in the track buffer172 and record buffer 152 for the purpose of implementing the inventivearrangements. Suitable software or firmware is provided in memory forthe conventional operations performed by control CPU 122. In addition,program routines for the advanced features 134 are provided forcontrolling CPU 122 in accordance with the invention as shallhereinafter be described in greater detail.

A control buffer 132 for viewer activatable functions indicates thosefunctions presently available, namely play, record, reverse, fastforward, pause/play and stop. The pause is a counterpart to pauseoperation in a VCR, for example manually interrupting the play back of aprerecorded program or interrupting the recording of a viewed program toeliminate commercials from the recording. A separate buffer 136 isprovided to receive commands for implementing the inventive arrangementstaught herein.

The video/audio input processing path 140 is a signal processing circuitfor converting a conventional television signal, for example NTSC orPAL, into digitized packet data, for example MPEG-1 or MPEG-2, fordigital recording by the device 100. The input path 140 comprises anNTSC decoder 142 and video encoder, for example MPEG-1 or MPEG-2, 144for video in, and comprises an audio analog-to-digital converter (A/D)146 and an audio encoder, for example MPEG-1 or MPEG-2, 148. Thedigitized signals are combined in a multiplexer 150 and stored in arecord buffer 152 until an entire packet has been constructed. As groupsof packets are constructed, they are combined with the output of thenavigation data generation circuit in the MUX 154 and sent to the errorcorrection coding circuit 128. Error correction coding circuit 128 canalso be deemed to be part of the input path 140.

As a practical matter, the smallest addressable unit on the spiral trackof a DVD is an ECC (error correction code) block of 16 sectors, whereeach sector includes 2048 bytes of user data. A group is a number of ECCblocks, for example 12. Each group of blocks represents approximately0.5 seconds of combined video and audio program material. The amount oflinear space along the spiral track needed to record a group of ECCblocks, for example 192 sectors, is defined herein as a segment of thespiral track. Accordingly, it can appear that the record buffer needs tobe only large enough to store one segment of data. One segment of datacan correspond, for example, to approximately 0.5 seconds of audio andvideo program material.

The output processing path 170 comprises error correction block 130 anda track buffer, or output buffer, 172, in which data read from the discis assembled into packets for further processing. The packets areprocessed by conditional access circuit 174 that controls propagation ofthe packets through demultiplexer 176 and into respective paths forvideo and audio processing. Accordingly, it can also appear that thetrack buffer 172 needs to be only large enough to store one segment ofdata, also corresponding to approximately 0.5 seconds of audio and videoprogram material.

The video is decoded by decoder 178, for example from MPEG-1 or MPEG-2,and encoded as a conventional television signal, for example NTSC orPAL. The audio is decoded by circuit 182, for example from MPEG-1 orMPEG-2, and converted to analog form by audio digital-to-analog (D/A)converter 184. The output processing path 170 can be deemed to includethe error correction circuit 130, as noted.

DVD Media

For purposes of illustrating the inventive arrangements, programmaterial can be recorded onto a rewritable DVD and played back from arewritable DVD. A rewritable DVD 10 shown in FIG. 2 is suitable for useas disc 102 in device 100. The disc 10 is formed by a flat, roundplastic plate-like member 12 having a hole 14 in the middle. Thedirection of recording on the track is typically outwardly along aspiral track 16, from a smaller radius part of the spiral to a largerradius part of the spiral. The several series of three large dots (_ __) denote portions of the track not shown in the drawing. As a result,the beginning of the spiral track is deemed to be near the hole 14, andis denoted by square 18. The end of the spiral is deemed to end near therim, and is denoted by diamond 20. Those skilled in the art generallyaccept defining the beginning and end of the spiral as noted. Certainadvanced features in accordance with the inventive arrangements utilizebackward recording, that is, from a larger radius part of the spiral toa smaller radius part of the spiral. The track can also have aside-to-side wobble, not shown in the drawing, to accommodate media typeindexing. Due to difficulties of scale only portions of the track 16 areshown, and these are shown in greatly enlarged scale.

Each nearly circular, radially concentric section of the spiral issometimes referred to as a track, but this terminology is not commonlyaccepted as having that specific meaning. In CD-ROM's, for example, theterm track is also used to refer to that portion of the spiral trackthat contains a single audio song, or other selection, and the same mayor may not become common for DVD's.

Various modifications of the device illustrated in FIG. 1 and the discmedium illustrated in FIG. 2 can be used together to implement theadvanced features taught herein in accordance with the inventivearrangements. It will be appreciated that the advanced features taughtherein are applicable to other kinds of disc media and disc mediaplayers and recorders.

As shown in FIG. 3, each DVD contains a video manager 26 and video titleset (VTS) 28. The VTS includes video title set information (VTSI) 27, anoptional video object set for menu 29, and one or more VOBS for title 30which contains the actual title content. Each VOBS 30 also includes aplurality of video objects 32. Each video object 32 includes a pluralityof cells 34. Each VOBS is comprised of a collection of pointers tocells. In this way, the VOBS data links cells together and indicates inwhat order the programs or cells are to be played. Cells within aparticular VOBS can be flagged for play in any desired order. Forexample, they can be played sequentially or randomly.

Each cell includes a plurality of VOBUs 36. Each of the VOBUs 36 inwhich the video content of the disc resides typically contains 0.4 to1.0 seconds of presentation material. Each VOBU 36 is a sequence of datapacks in recording order. Each VOBU starts with exactly one navigationpack (NV_PCK) 38 and could encompass all of following kinds of packs,including video packs (V_PCK) 39, audio packs (A_PCK) 40 and sub-picturepacks (SP_PCK) 42. Each VOBU is nominally comprised of one group ofpictures (GOP).

The NV_PCK 38 contains presentation control information as well as datasearch information. The data search information is useful in performing“trick” modes of playback, that is, any mode of DVD device operationother than normal play, stop and pause. One aspect of data searchinformation (DSI) is that it helps the decoder to find referencepictures within the VOBU corresponding to the current NV_PCK. Anotheraspect of the DSI is that it helps the decoder to find VOBUs far intothe future or past of presentation, relative to the current VOBU. TheVOBUs in the past relative to the current VOBU presentation arereferenced in fields of the NV_PCK known as the BWDI (backwardinformation). The VOBUs in the future relative to the current VOBUpresentation are referenced in fields of the NV_PCK known as FWDI(forward information).

Each VOBS can include navigation commands which permit branching orother interactive features. These navigation commands can be included aspart of the VOBS as a set of pre-commands. These pre-commands can befollowed by optional navigation commands identified within the NV_PCK 38of the cells 34, which commands are executed after the cell ispresented. Finally these may be followed in the VOBS by an optional setof post-commands. All of these commands are stored in a table within theVOBS and can be referenced by number so that they can be usedrepeatedly. The navigation commands can direct the control CPU 122 toperform a variety of operations associated with branching or interactivefeatures. For example, they can provide flow control with commands suchas goto, link, jump, exit, and so on.

A menu is a set of buttons which can permit a user to control a videopresentation. Information to create menu buttons is included in thecommand data. Buttons can be drawn on the video background of a display,and DVD allows control over the appearance of the buttons. Invisiblebuttons can be created by setting the pixel contrast to zero. Eachbutton has a command with which it is associated. In most instances,these will be flow control commands as described above. For the purposeof accessing a plurality of VOBS 30 on a disc containing different videopresentations, a menu construct can be provided in the VOBS for menu 29.The menu in this case has navigation commands associated with each ofthe buttons of the menu.

Three-Stage Menu Processing for DVD Recorder

The present invention makes use of three-stage menu processing to solvethe problems that make real-time generation of navigation menusdifficult in recordable DVD. FIG. 8 is a flowchart useful forillustrating the process. The first stage involves preprocessing of amenu. In step 80, a pre-created template menu can be provided orselected by a user with a set of hidden or invisible buttons. The usercan select the number of buttons to be associated with the templatemenu. Further each of the buttons may have certain languages associatedwith it. For example, to facilitate use in various regions of the world,the language associated with the buttons may include English, Spanish,or French. The template menu is preferably stored in memory, or can becreated by embedded software in the DVD player.

Each button associated with the template menu preferably has dummy(i.e., empty) command(s) pre-recorded therewith or no commands at all.The template buttons are initially configured such that when thesebuttons are activated, the software commands, if any, associatedtherewith will be of no consequence and will have no effect. Further,the buttons in the template menu are preferably configured so that theyare hidden and are therefore not displayed. Thus, the template menu 44initially appears as an essentially blank screen as shown in FIG. 4.

In the second stage, if a menu is needed during recording, thepre-created template menu 44 can be copied to a location on the disc forthe VOBS for menu 29. Subsequently, the recording process can begin instep 82. In step 84, the control CPU 122 determines whether a markingcommand has been detected. If the marking command is detected by controlCPU 122 in step 84, it causes a non-dummy command, such as a flowcontrol command, to be associated with one of the existing hiddenbuttons. The marking command will cause a record to be made of thelocation in the bit stream corresponding to the point in time when themarking command was received. The non-dummy command associated with themenu button can be configured to reference the recorded location in thebit stream for allowing subsequent accessing of video data recorded atthat location on the disk.

The marking command can be initiated by any suitable means. For example,the user can activate a control button for the DVD device 100 or thecommand could be automatically initiated by a software program routinefor controlling the operation of control CPU 122. Such a marking commandcan be input by means of a suitable user interface operatively connectedto advanced feature buffer 136. If a software routine is used for thispurpose, then under certain predefined conditions, such as each time arecording session of some length is begun, the marking command can begenerated. As a result of the marking command, the system proceeds tostep 86 and one of the dummy buttons on the template menu 44 will becomevisible and navigable.

FIG. 5 illustrates a template menu 44 after one buttons 45 has beenactivated. In particular, the pixel contrast of the button has beenchanged to some value other than zero so that it is visible on screen.In addition, a valid navigation or flow control command is now assignedto the button, replacing the dummy command, if any. FIG. 6 illustratesthe same menu 44 after six of the buttons 45 have been activated so thateach is now visible and assigned a valid flow control command which willcause the DVD player 100 to jump to the scene which has been marked.

When the recording session is completed as determined in step 88, thethird stage of the process can begin. In the third stage, subsequent torecording the video presentation material and marking any presentationsas described above, the menu 44 can be modified as desired in step 90.For example, the menu name 46 can be changed and the particularappearance of the buttons can be altered as shown in FIG. 7. Accordingto one embodiment of the invention, the buttons can be made to appear asthumb-nail still images. For example, the thumb-nail image can be thefirst picture associated with the recording to which the buttons willcause the player to jump. The background 47 for the menu 44 can also bechanged to an appearance selected by the user.

Alternatively, a button can be removed from the menu by deleting thevalid flow control command or converting the command back to a dummycommand. If no non-dummy commands associated with a button exist, thebutton will become invisible and non-navigable. If necessary, thelanguages on the menu and the content of the menu can also be alteredafter recording.

According to a further aspect of the invention, if the number of buttonsnecessary to access the various video segments exceeds the amount ofspace practically available on the menu, then a second menu screen canbe automatically added to include the additional buttons. The secondmenu screen can be accessed, for example, by a “next menu” button whichcan be included on the first menu screen.

The inventive arrangements provide great user flexibility to enablepersonalized menus to be added to recordings. Separating the menuprocessing into three stages, namely pre-processing, recording, andpost-processing, in accordance with the inventive arrangements providesenhanced user convenience and flexibility.

1. A method for real time generation of menus in a DVD recordercomprising the steps of: providing a template menu having at least onedummy button; activating a marking command during a video data recordingsession; and responsive to said marking command, modifying said templatemenu by assigning to said dummy button a valid flow control command foraccessing said video data which has been recorded at a timecorresponding to said activating step.
 2. The method according to claim1 further comprising the step of storing said template menu on said DVDprior to said recording session.
 3. The method according to claim 1further comprising the step of controlling a display parameter of saiddummy button responsive to said marking command to make said dummybutton visible.
 4. The method according to claim 1 further comprisingconfiguring said template menu with a selected number of dummy buttonsresponsive to a user input.
 5. The method according to claim 1 furthercomprising the step of modifying said template menu after said videodata recording session.
 6. The method according to claim 5 wherein atleast one of a button language, button appearance, button text, menuname and menu background is modified.
 7. The method according to claim 5wherein said modifying step comprises changing the appearance of abutton to a thumb-nail image.
 8. The method according to claim 7 whereinsaid thumb-nail image is a scene determined by said video data recordedduring said session.
 9. The method according to claim 8 wherein saidmodifying step comprises deleting a button.
 10. The method according toclaim 1, further comprising providing a second template menu accessiblefrom said first template menu if additional buttons are needed.
 11. Asystem for real time generation of menus in a DVD recorder comprising:means for providing a template menu having at least one dummy button;means for activating a marking command during a video data recordingsession; and means responsive to said marking command, for modifyingsaid template menu by assigning to said dummy button a valid flowcontrol command for accessing said video data which has been recorded ata time corresponding to said activating step.
 12. The system accordingto claim 10 further comprising means for storing said template menu onsaid DVD prior to said recording session.
 13. The system according toclaim 10 further comprising means for controlling a display parameter ofsaid dummy button responsive to said marking command to make said dummybutton visible.
 14. The system according to claim 10 further comprisingmeans for configuring said template menu with a selected number of dummybuttons responsive to a user input.
 15. The system according to claim 10further comprising means for modifying said template menu after saidvideo data recording session.
 16. The system according to claim 14wherein at least one of a button language, button appearance, buttontext, menu name and menu background is modified.
 17. The systemaccording to claim 14 wherein said modifying step comprises changing theappearance of a button to a thumb-nail image.
 18. The system accordingto claim 16 wherein said thumb-nail image is a scene determined by saidvideo data recorded during said session.
 19. The system according toclaim 17 wherein said modifying step comprises deleting a button. 20.The system according to claim 11 further comprising means forautomatically providing a second template menu if additional buttons areneeded.